package com.sky.interceptor;

import com.alibaba.fastjson.JSONObject;
import com.sky.constant.JwtClaimsConstant;
import com.sky.context.BaseContext;
import com.sky.exception.BaseException;
import com.sky.handler.GlobalExceptionHandler;
import com.sky.properties.JwtProperties;
import com.sky.result.Result;
import com.sky.utils.JwtUtil;
import io.jsonwebtoken.Claims;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * jwt令牌校验的拦截器
 */
@Component
@Slf4j
public class JwtTokenAdminInterceptor implements HandlerInterceptor {

    @Autowired
    private JwtProperties jwtProperties;

    /**
     * 校验jwt
     *
     * @param request
     * @param response
     * @param handler
     * @return
     * @throws Exception
     */
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //每次请求都对应着不同的线程
        System.out.println("当前线程的Id："+Thread.currentThread().getId());

        //判断当前拦截到的是Controller的方法还是其他资源
        if (!(handler instanceof HandlerMethod)) {
            //当前拦截到的不是动态方法，直接放行
            return true;
        }

        //1、从请求头中获取令牌
        String token = request.getHeader(jwtProperties.getAdminTokenName());

        //2、校验令牌
        try {
            log.info("jwt校验:{}", token);
            //如果jwt解析报错说明token有误，解析失败
            Claims claims = JwtUtil.parseJWT(jwtProperties.getAdminSecretKey(), token);
            Long empId = Long.valueOf(claims.get(JwtClaimsConstant.EMP_ID).toString());
            log.info("当前员工id：", empId);
            //可利用ThreadLocal作为一次请求的共享空间，保存拦截器中从JWT解析出来的ID
            BaseContext.setCurrentId(empId);

            //3、通过，放行
            return true;
        } catch (Exception ex) {
            //4、不通过，响应401状态码
            response.setStatus(401);
//            throw new BaseException("jwt校验错误");
            ex.printStackTrace();
            log.info("解析令牌失败, 返回未登录错误信息");
            Result error = Result.error("NOT_LOGIN OR JWT ERROR");
            //手动转换 对象--json --------> 阿里巴巴fastJSON
            String notLoginJson = JSONObject.toJSONString(error);
            response.getWriter().write(notLoginJson); //将登录的错误信息响应给前端
            return false;
        }
    }
}
